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Netlab Reference Manual som
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<H1> som
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<h2>
Purpose
</h2>
Creates a Self-Organising Map.

<p><h2>
Synopsis
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<PRE>

net = som(nin, map_size)
</PRE>


<p><h2>
Description
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<CODE>net = som(nin, map_size)</CODE> creates a SOM <CODE>net</CODE>
with input dimension (i.e. data dimension) <CODE>nin</CODE> and map dimensions
<CODE>map_size</CODE>.  Only two-dimensional maps are currently implemented.

<p>The fields in <CODE>net</CODE> are
<PRE>

  type = 'som'
  nin = number of inputs
  map_dim = dimension of map (constrained to be 2)
  map_size = grid size: number of nodes in each dimension
  num_nodes = number of nodes: the product of values in map_size
  map = map_dim+1 dimensional array containing nodes
  inode_dist = map of inter-node distances using Manhatten metric
</PRE>


<p>The map contains the node vectors arranged column-wise in the first
dimension of the array.

<p><h2>
See Also
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<CODE><a href="kmeans.htm">kmeans</a></CODE>, <CODE><a href="somfwd.htm">somfwd</a></CODE>, <CODE><a href="somtrain.htm">somtrain</a></CODE><hr>
<b>Pages:</b>
<a href="index.htm">Index</a>
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<p>Copyright (c) Ian T Nabney (1996-9)


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